The Hejaz (or Hedjaz or Hijaz) railway is a narrow-gauge railway (1,050 mm / 3 ft 5 11⁄32 in track gauge) that runs from Damascus to Medina, through the Hejaz region of modern day Saudi Arabia, with a branch line to Haifa on the Mediterranean Sea.

It is a part of the Ottoman railway network and the original goal is to extend the line from the Haydarpaşa Terminal in Kadikoy beyond Damascus to the holy city of Mecca.

However, construction is interrupted due to the outbreak of the First World War, and it reached no further than Medina, four hundred kilometres (two hundred and fifty miles) short of Mecca.

The completed Damascus to Medina section is thirteen hundred kilometers (eight hundred and ten miles).

The main purpose of the railway is to establish a connection between Constantinople, the capital of the Ottoman Empire and the seat of the Islamic Caliphate, and Hejaz in Arabia, the site of the holiest shrines of Islam and the holy city of Mecca, the destination of the Hajj annual pilgrimage.

Another important reason is to improve the economic and political integration of the distant Arabian provinces into the Ottoman state, and to facilitate the transportation of military forces.